Wave soldering is a widely used technique for high volume soldering of printed circuit boards and the like. One of the problems encountered is the formation of oxides of the tin, lead and other components of the solder. This leads to increased surface tension of the solder and, thereby, to increase bridging. U.S. Pat. No. 3,705,457 issued to Tardoskegyi discloses a method of reducing this problem by aiming a stream of inert gas at the area in which the molten solder and the workpiece intersect, thus inhibiting oxidation. However, this is a relatively complex apparatus requiring fine alignment and does not completely preclude oxidation.
Another disadvantage of present wave soldering techniques involves the use of flux to improve the quality of the solder joints. The flux can contaminate some parts, requiring careful application of the flux and cleaning after the soldering operation.